/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.optimize.peephole;

import proguard.classfile.ClassConstants;
import proguard.classfile.Clazz;
import proguard.classfile.ProgramClass;
import proguard.classfile.util.SimplifiedVisitor;
import proguard.classfile.visitor.ClassVisitor;
import proguard.optimize.info.WrapperClassMarker;

/**
 * This ClassVisitor inlines the wrapper classes that it visits into their wrapped classes, whenever possible.
 *
 * A wrapper class can be a simple (anonymous) inner class that implements some interface, for example.
 *
 * @see WrapperClassMarker
 * @see ClassMerger
 * @author Eric Lafortune
 */
public class WrapperClassMerger extends SimplifiedVisitor implements ClassVisitor {
    private final boolean allowAccessModification;
    private final ClassVisitor extraClassVisitor;

    /**
     * Creates a new WrappedClassMerger.
     *
     * @param allowAccessModification specifies whether the access modifiers of classes can be changed in order to merge
     *        them.
     */
    public WrapperClassMerger(boolean allowAccessModification) {
        this(allowAccessModification, null);
    }

    /**
     * Creates a new WrappedClassMerger.
     * 
     * @param allowAccessModification specifies whether the access modifiers of classes can be changed in order to merge
     *        them.
     * @param extraClassVisitor an optional extra visitor for all merged classes.
     */
    public WrapperClassMerger(boolean allowAccessModification, ClassVisitor extraClassVisitor) {
        this.allowAccessModification = allowAccessModification;
        this.extraClassVisitor = extraClassVisitor;
    }

    // Implementations for ClassVisitor.

    public void visitProgramClass(ProgramClass programClass) {
        // Only merge wrapper classes that extend java.lang.Object.
        if (ClassConstants.NAME_JAVA_LANG_OBJECT.equals(programClass.getSuperName())) {
            // Do we have a wrapped program class?
            Clazz wrappedClass = WrapperClassMarker.getWrappedClass(programClass);
            if (wrappedClass instanceof ProgramClass) {
                // Try inlining the wrapper class into the wrapped class.
                new ClassMerger((ProgramClass)wrappedClass, allowAccessModification, false, true, extraClassVisitor)
                    .visitProgramClass(programClass);
            }
        }
    }
}